Every god recieves a pile of coins that bear his mark. These are given by Mawhiti since he organised the game.
The gods make tests (traps/puzzles/monsters/riddles/ etc.) and award champions of rival gods that overcome them with coins.
So your god wants a champion he deems fitting and sends that champion out to other gods domains. And he builds tests to test other champions.

After most gods have champions we'll start opening portals for tests.

An example here would be to throw a few coins in a dragons hoard. Or give a coin to a group of wicked witches.
Or you could bury the coins deep in a temple full of traps and puzzles.

Whatever would make an epic story really.